RELATED ARTICLES

Share this article

If someone wants to view the photo at a later date, the server checks whether the key has expired. If it has, the photo is blocked and cannot be displayed.

Mr Backes said that while social network users currently have the ability to delete photos from sites like Facebook, most 'don't get round to it'.

'Most Facebook users, for example, are passive users,' he said.

'They go on, they put on a lot of private information and almost never come back on or they forget their password.

'The software is not designed for people who understand how to protect their data but rather for the huge mass of people who want to solve the problem at its core and not to have to think about it any more.'

However, Mr Backes warned that third parties can still view and save users' photos while they are in the valid time period.

He added: 'When people put photos on line, it's so they can be seen. Our software is not a panacea, not absolute protection.'